1. Field of the Invention
The present invention generally relates to an operating method of a hard switch, and more particularly, to and an operating method of a hard switch of a die stack.
2. Description of Related Art
With a progress in technology of die manufacturing, dies having different functions or differently processed are integrated by vertically stacking to deal with the issue in manufacturing transistors having different functions or differently processed in a single die. However, signal transmission paths in current die stacks are simply formed by configuring signal pads in redistribution layer (RDL) to change positions thereof in front or back of the dies. Next, the dies are connected through micro bumps therebetween in the die stack. Accordingly, signals are transmitted between the dies sequentially through wires, pads, micro bumps, and through silicon vias (TSVs) in a vertical direction thereof. Generally, due to the configuration in the above-described technology, signal transmission modes may be fixed between the dies in the stack. That is, when different designs of the signal transmission modes are required, the micro bumps or the wires configured in redistribution layer in front and back of the die need to be changed to satisfy the requirement.